Transformer Load & Power Consumption Chart
Excerpt from HOW TO OPERATE YOUR LIONEL TRAINS, 1959, Page 52
How To Estimate Available Power:
The wattage rating of a transformer tells you how much power it will take from
your household mains. However, all of this power is not available for your
train. From about one-quarter to one-eighth of the total wattage taken from the
lines is used up by the transformer itself in transforming the power from high
to low voltage. This wattage loss becomes apparent in the warming up of the
transformer as it is used.
A transformer operating continuously for long periods of time or in warm
surroundings will be able to deliver less power than one used intermittently or
in cool surroundings. As the transformer warms up in use its output voltage and
wattage will drop gradually.
As an example, a 90-watt No. 1033 transformer should not be used to deliver more
than 60 watts of usable low-voltage power. A 275-watt ZW transformer should not
be counted on to supply more than 200 watts. It is important to take this loss
into consideration when estimating the amount of equipment your transformer can
operate.
Another and simpler way to determine the amount of equipment which you can add to your train layout is by considering the amount of current, in amperes, which can be supplied by your transformer continuously, without overheating. The following table lists the current which can be supplied by Lionel transformers for at least four hours of continuous operation, under normal temperature conditions.
| Transformer | Max. Output Amps |
|---|---|
| 1015 | 2.5 |
| 1043-1053 | 3.0 |
| 1033-1044 | 4.0 |
| LW | 5.5 |
| KW | 8.0 |
| TW | 8.0 |
| ZW | 12.0 |
How To Estimate Your Power Requirements
While electric power is normally calculated in watts, you can obtain a very
close approximation of the requirements of your model railroad by adding up the
current, in amperes, consumed by your equipment, counting 1-1/4 amperes for each
motor, and 1/5 amperes for each steadily burning lamp.
You do not need to figure in the power requirements of automatic couplers and
operating cars, since the couplers draw current for only an instant and
operating cars only when the train is not running. For the same reason, do not
add power used by such accessories as coal elevators, log loaders and other
operating devices which are put in action when the train is not running.
Even with a small transformer your layout can contain as many operating
accessories as you wish provided that you operate them one at a time.
For example, if your outfit consists of a 5-car illuminated passenger train
pulled by an "O" gauge twin-motored locomotive, and you have a pair of No. 022
switches, 4 lamp posts and a couple of block signals you could make a table, as
follows:
| Equipment | Quantity | Current | Total Amps |
|---|---|---|---|
| Motors | 2 | 1.25 | 2.5 |
| Headlights | 2 | 0.2 | 0.4 |
| Car Lights | 10 (2 in each) | 0.2 | 2.0 |
| Switch lights | 2 | 0.2 | 0.4 |
| Switch controllers | 2 | 0.2 | 0.4 |
| Block Signal lights | 2 | 0.2 | 0.4 |
| Total current | 6.1 amps |
This would mean that your outfit would require a continuous current of
approximately 6 amperes and would call for a KW or a TW transformer.
Again, note that installation of several operating units such as a No. 356
Station and a No. 350 Transfer Table will have practically no effect on your
power requirements.